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Diffstat (limited to 'testsuite/tests/driver/implicit-dyn-too/QuasiExpr.hs')
-rw-r--r-- | testsuite/tests/driver/implicit-dyn-too/QuasiExpr.hs | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/testsuite/tests/driver/implicit-dyn-too/QuasiExpr.hs b/testsuite/tests/driver/implicit-dyn-too/QuasiExpr.hs new file mode 100644 index 0000000000..d81fcf8b05 --- /dev/null +++ b/testsuite/tests/driver/implicit-dyn-too/QuasiExpr.hs @@ -0,0 +1,35 @@ +{-# LANGUAGE Haskell2010 #-} +{-# LANGUAGE TemplateHaskell #-} + +-- Used by QuasiQuote. Example taken from the GHC documentation. +module QuasiExpr where + +import Language.Haskell.TH +import Language.Haskell.TH.Quote + +data Expr = IntExpr Integer + | AntiIntExpr String + | BinopExpr BinOp Expr Expr + | AntiExpr String + deriving Show + +data BinOp = AddOp + | SubOp + | MulOp + | DivOp + deriving Show + +eval :: Expr -> Integer +eval (IntExpr n) = n +eval (BinopExpr op x y) = (opToFun op) (eval x) (eval y) + where + opToFun AddOp = (+) + opToFun SubOp = (-) + opToFun MulOp = (*) + opToFun DivOp = div + +expr = QuasiQuoter parseExprExp undefined undefined undefined + +-- cheating... +parseExprExp :: String -> Q Exp +parseExprExp _ = [| BinopExpr AddOp (IntExpr 1) (IntExpr 2) |] |